擅长:python、mysql、java
<p>您必须遵循以下步骤:</p>
<ol>
<li><p>首先找到CSV文件的长度,而不将整个CSV文件加载到ram中。
必须在read_csv()中使用chunksize。在</p>
<pre><code>import pandas as pd
count = 0
for data in pd.read_csv('YourFile.csv',encoding = 'ISO-8859-1',chunksize = 1000):
count += 1 # counting the number of chunks
lastlen = len(data) # finding the length of last chunk
datalength = (count*1000 + lastlen - 1000) # length of total file
</code></pre></li>
<li><p>Second减去要读取的行数。在</p>
<pre><code>rowsdiff = datalen - 300
df = pd.read_csv('YourFile.csv',encoding = 'ISO-8859-1',skiprows = range(1,difrows), nrows = 299)
</code></pre></li>
</ol>
<p>通过这种方法,您只需读取最后几行,而不必将整个CSV文件放入ram中</p>